Track roller seal construction



Nov. 14, 1939. o. B. BAKER ET AL 2,180,134

TRACK ROLLER SEAL CONSTRUCTION Filed March 5, 1937 jnz/eni'ors fiaafi aq'ffordfifogers *Zz/L'ZZamz Qfiec/m m Patented Nov. 14, 1939 UNITED STATES PATENT OFFICE assignors to International Harvester Company, a corporation of New Jersey Application March 5, 1937, Serial No. 129,168

3 Claims.

This invention relates to the construction of track rollers or the like utilized in crawler tractors to transmit the weight of the tractor to the ground run of the endless tractor belt. More particularly, the invention relates to a seal mechanism disposed between respective ends of the track roller and the shaft on which the roller turns, to insure thatdirt and dust from the outside cannot find ingress to the bearing surfaces on which the roller turns, and that oil from within the roller, that lubricates the bearing surfaces, cannot seep out. The fact that these track rollers are under heavy loadmakes it necessary that the bearing surfaces on which the roller turns be properly lubricated and protected from wear, caused by the entry of extraneous abrasive matter.

The object of the invention is the provision of a track roller structure with seals effective to retain oil within the structure and to keep dirt from entering.

These track rollers are carried on a stationary shaft and secured horizontally between the sides of a so-called track roller frame by means of 5 brackets which serve to fix the shaft in the frame. The improved seal structure of this invention is arranged between the respective ends of the roller and the adjacent end of said bracket, as will hereinafter appear.

The improved track roller seal construction is shown in the accompanying sheet of drawings, wherein:

Figure 1 is a cross-sectional view through so much of the track roller and the support structure therefor as is necessary to disclose the invention; and,

Figure 2 is a similar cross-sectional view fragmentarily showing a modified form of seal.

In the track roller construction there is utilized a track roller frame I0 having opposite side channel members ll, only one of which is shown. A round shaft I2 is horizontally disposed and has reduced ends 13 semicircularly shaped with an upper fiat edge l4 that is placed flatly under the lower flange of the frame channel H. A bracket 15 including a bolt [6 is used to rigidly clamp the reduced semicircular end I3 of the shaft ii! to the under side of the lower flange of the channel frame member II. In this fashion the shaft I2 is held stationary in the frame II. This shaft, midway between its ends, is formed with an upset radial flange I1, and the shaft is formed with a central bore I8 including a radial bore H, which extends vertically upward through the flange H, as shown. One

end of the passage it? carries a fitting 28 whereby suitable lubricant may be forced into the bore I8 of the shaft to load the same with lubricant, as will later appear. Radial passages 2! from the passage iii are also provided in the shaft l2. The bracket I5 is carried below the frame I! and includes an annular channel-shaped rim portion 22 and around the shaft [2 in spaced relation thereto. Surrounding the shaft I2 on each side of the flange ii are bearings 23, and 10 disposed on these hearings are carriers 24, which are circular, and to the outer periphery of which are tightly fitted, as by shrinking thereon, the

track roller 25 a snap ring 26 being provided to hold the roller 25 and carrier 24 against rela- 15 tive axial shifting movement. It will be noted I that the outer face of the carrier 24 is provided with an annular passage or reentrant portion 2%,, which telescopically fits over the channelshaped rim 22 of the bracket 15. The fit of the 20 rim 22 within the portion 26 is sufficiently close though without contact and the overlap of the parts is considerable so that there is a running tolerance seal formed at this point even without the aid of other seals. A pack of fiat felt, or 25 other fiber, washers 21 is located between the outer side of the passage 26' and the inner adjacent side of the channel rim 22. It will be noted that the carrier 24 has an axial extension or rim portion 28 which forms a channel-shaped 3c annular space 29 in which is placed another pack of felt or the like washers 30, said washers being located within the inner diameter channel of the rim 22 and around the hub portion 28 of the carrier 24. At the outer edge of the annular 35 hub portion 28 and the adjacent inner face of the bracket l5 is another pack of flat fiber or felt washers 3!. Between the rim portion 28 and the shaft [2, the carrier 24provides an annular passage 32 surrounding the shaft, in which 40 is located another seal 33 of the unitary type, which includes an annular leather 34 and a second annular leather 35, these leathers constituting seal elements flexibly engaging the periphery of the shaft I2. 40

In Figure 2, a slight modification of the seal structure is shown in that the laminated felt washer seal pack 3| is shown at 3| and its outer diameter is retained by a channel-shaped metallic rim 36, which is L-shaped in cross-section, as shown, better to locate the said laminated fiber washer pack 3|. It will be noted in Figure 2 that all of the other parts correspond identically with the showing in Figure 1, and the same reference characters have been used with the addition of an exponential prime.

The opposite side of the track roller construction is the same as that shown in the drawing, as will, of course, be understood. By means of a grease gun, or the like, the nipple 20 is used to load the passage I8 with oil, which also is forced up the passage l9 and into the space between the opposite two carriers 24 inside the roller 25. This oil passes by gravity to the thrust surface on the flange I 1, against which the inner ends of the two opposite carriers 24 abut, and. also by means of the radial passages 2| it passes by gravity to the needle bearings 23 to lubricate this bearing surface. The oil, if it is to seep out, must pass the two leathers 34 and 35 of the double rawhide seal unit 33, and thence past the laminated felt or fiber seal pack 3| or 3|. Dust cannot get into the bearings 23 without having to pass from the outside into the space 26 and past the fiber pack 2|, and then past the tortuous passage formed by the channel rim 22 or 22', and then past the fiber pack 30 or 30', as well as the fiber pack 3| or 3|.

It can now be seen that an improved seal structure has been provided for track rollers and the like of the type described which achieves the object of keeping the oil in and dirt out, thereby serving to cause the roller to operate efiiciently and have a long and satisfactory life.

It is the intention to cover herein all changes and modifications of the example of the invention herein shown for purposes of illustration which do not in material respects constitute departures from the spirit and scope of the invention.

What is claimed is:

In combination, a stationary shaft, a first member secured to the shaft, said member including an annular part provided with a channel on the inner surface thereof, a second rotatable member journaled on the shaft, said rotatable member having its end face adjacent the first member formed with a reentrant groove into which the annular part of the first member extends so as substantially to form an enclosed space, a seal in the space, said rotatable member on the same face also having a hub portion spanning the channel on the inner surface of the annular part, and a seal in the channel of the annular part surrounding the hub portion.

2. In a construction comprising a stationary shaft, a stationary member surrounding the shaft, and a rotatable member journaled on the shaft, the combination with a portion of the rotatable member having a reentrant groove in the side thereof, of a portion of the stationary member of substantially the Width of and fitting into the reentrant groove in the rotatable member so as to form an enclosed space, and

a seal within said space.

3. In combination, a stationary shaft, a first member secured to the shaft and including an annular part provided with a channel on the inner surface thereof, a second rotatable member journaled on the shaft, having a portion fitting within the annular part of the first member so that the channel in the annular part and the portion of the rotatable member form an enclosed space, a seal in the space, said rotatable member also having a reentrant groove in the side thereof into which the annular part extends so as to form an enclosed space, and a seal in the space, the fit of the annular portion of the stationary member within the reentrant groove being sufficiently close and the overlap of the parts being considerable so as to provide a running tolerance seal.

DAVID B. BAKER. CLIFFORD R. ROGERS. WILLIAM O. BECHMAN. 

